Back-spacing mechanism for typewriters



' v 1,639,199 Aug- 16 1927' H. PEETERS BACK SPAGING` MEGHANISM FOR TYPEWRITERS Filed Feb, 20. 1924 Patented Aug. 16, 17927.

a UNITED STATES PATENT VI-IIEIRY PEETERS, OF WARCOING, BELGIUM.

BACK-SPACING MECHANISM Fon 'TYPEWRITERs V,application filed February zo, 1924, serial No. e94;o7s, an m Belgium December 21, 1923.

This invention relates vto an improvement in the mechanisnrf'or the return of the paper carriage for typewriters iin which the said movement is controlled by a leverfoperated by hand, :and the `invention Yrelates more particularly. to a inecli'anisrn which allows the carriage to be lnoved in the direction opposite to' that :which corresponds to the automatic advance for typing,'to- 'a given 'diste-nce which is generally that of a eher'- acter to be printed, or of a space.

*In 'knowndevices-ot this/type the appr'o'aeh of -the rck toward' the finger is produce-d- 'hy displcing i-t in a direction which is inclined relative to 'the a-Xs of 'the or else'. itis-produced by the intermediary of a; complicated inecfllianisrn. The interengagenlient of'fthe linger bythe rack is, therefore-,not directfnd as l'a result of this, after seine little usage, tlie linger fno longer ngages behind the desired tooth 'of the rc'k which is 'actuated vby pnshing and thns renders the mechanism uncertain.' Further'- Inofrel, at very high speeds, vdue to the haste of `the operator, vor ydue to the effect of the back spacing rno'ven'ien-t, which fthe carrie-:ge

undergoes-in 'fcontactihg against -a stop, it

may occur tlratftlie raeli VwillContactv with the linger in an unforeseen position.

In am persen' meteen the displacementof' the rack towardv the finger is' produced by a hand lever inadireeti'on'perpendicular to its vairis, wlfiile the lnove'fnent in the baok spate dire'c'tionof the c'arriafge is produee'd by a'nrechnisxn w'liich'is "lutonratic and is iii-dependent of the seiddever.

For this purpose, according to, the inve'nf.

tion, l:this handA y lever can movev Vangdlarly along 'agraduatfedscele while drawing rvalong thel spindle which causes theJ engagement of.

the"'rckHwith-the finger, 'and' which moves vthei'n backwards a distance'corresponding 4to the angular :displacement of the hand lever. n

fback to a length corresponding'vto that 'of' a. Jcharacter,"the spindle 153 is turned inthe This return'inovernent is prodced'xas soon as la bell'fcrank' lfeveigfpivoted to thesuppo'rt of" 'the raclyand "engaged'by 4rnovalbl'e, spindle,A pushes gainfstfa liXed z'ibntnie'nt. A

een is 'ineen-ated byxvay or exemple muy@ igure'B is la iear vieri-*ofthe device vShown in Figure Q, showing 'the position of the' various elements during vtheir operation.

VEig. 4 is e perspeetive View showing the verrons 'elements of a constrnetienal v'form of the invention permitting a variable back spaeingof the 4a-rria-g`e. i A i In the drawings is represented 'one form A of the invent-ion, kift-being Clearly understood f means of handle 121 opera-tes the interlinngV mechanism. These rods 117 and 106 are interconnected by a collar meniberllS so as to be nioved together bodily, while being independently' roclr'a'ble.

On 4a se'oiid men'ib'er (notshown) similar to 118", isy rnnnte'da pointer 136 v'travelling in a groove 137 front of a gradn'ated rule or scale. 188k measuring the ktlrav'el of the carriage. y j: f Y Y The Vpointer 136 projects downwards in the 'forni of a finger which during th'e o moxfeihent ol1 the earriagenioves near a' rack l 151, the teeth or 'winch corresponds t@ 'the lengths of thel spaces rand which `is' 'suported' by 'a rod 152 "along which 'it slides. This rod '152 is keyed by In'eans of the arin- 154 to api'vot'e'd spindle 153 mounted on themain i franiefthe niacl'iinethe rotation of the said spindle in the. direction indicated by the direct-ion indicated ow'i'ng to which the rack 1,51 is brought into contact with" the vfnger 15() supported. 'by the rods, 106, 1'17frigidly connected to `the carriage. The finger 150 engages behind the tooth of the ra`ek`151',

which fis in the saine vertical plane. At that montrent, the bell-crank lever 156 pivoting about the spindle 157, strikes the stop 158 and pushes infront "of it the 'rack ll'along the rod-'152 lv vh''ch drives the control piece constituted by the rods 106, 117 to a distance corresponding to a space.

The device thereupon automatically resumes the original position under the action ol` the two springs 159-160.

Obviously, the amplitude of the movement depends more particularly on the shape or" the lever 155, and the said shape is such that by turning the spindle 153 to the end of the travel, the carriage is pushed back to the eX- tent of a length of a character. There characters ot different lengths are utilized, as is the case in some oriental languages, the pivoting of the spindle 153 may be effected in such a manner that, by moving the handle in lront of a series ot marks, the carriage is moved back to a length corresponding to one, two or more spaces. In order that this take place it is evident that the linger 150 cannot rpass to the bottom of the notches separating the teeth of the rack 151. A rack having notches of sullicient depth is shown in Figure 4. rlhe drawing shows one form or" this means, wherein is a graduated scale 161 on which are graduations according to which the lever 155 should be moved, for backspacing the carriage, one, two, or more spaces. This formv is purely illustrative, and presents the disadvantage that there are no limiting means for predetermined movements ot lever 155. Oli course this simple i'orm can be replaced by any ot the well known means for limiting the movement of lever' 155. tiple combinations may be made, without departing from the invention, as regards the shape and the arrangement ot the parts.

What I claim .as my invention and desire to secure by Letters Patent is:

1. A back spacing mechanism tor typewriters, comprising a linger rigidly connected to the carriage of the typewriter, a rack normally out ol' engagement with the linger, an elongated rod slidably carryingv the rack, a han-d lever operable to move this rod and the raclr normally towards the linger until engagement between the linger and the rack is produced, and means carried by the rod for sliding the rack along its rodafter said engagement, the displacement of the hand lever being continue-d. l

2. A back spacing mechanism l'or typewriters, comprising a linger rigidly connected to the carriage ofk the typewriter, a rack normally out ot engagement with the linger, an elongated rod slidably carrying the rack, a hand lever operable to move this rod and the rack normally towards the linger until engagement between the linger andthe rack is produced, a bell-crank lever mounted on the rod and arranged to bear against the rack, a fixed stop adjacent the bell-crank lever, the bell-crank lever being brought to bear against the stop simultaneously with the interengagement ol the linger and rack Furthermore, it is clear that multo thereby cause a movement oli' the rack and linger in the back spacing direction of movement of the carriage, the displacement of the hand lever being continued.

3. A back spacing mechanism for typewriters, comprising, a linger rigidly ,connected to the carriage of the typewriter, an elongated rod, a rack carried by this rod and slidable lengthwise of the same, a spindle parallel with the rod, an arm interconnecting the spindle and rod, a liXed stop, a hand lever for rocking the spindleLa pivoted bellcrank lever bearing at times against one end of the rack and the fixed stop, rocking ot the spindle by the hand lever moving the rack to engage the linger normally therewith and simultaneously press the bell-crank lever against the stop to thereby slide the rack along the rod, and resilient means for returning the rack and hand lever to their initial positions.

4. A back spacing mechanismv for typewriters, comprising, a lingerV rigidly connected to the carriage of thel typewriter, an elongatedrod, a rack carried by this rod and slidable lengthwise of the same, a spindle parallel with the rod, an arm interconnecting the spindle and rod, a lixed stop, a hand lever for rocking the spindle, a pivoted bell-crank lever bearing at times against one end of the rack and the Xed stop, rocking of the spindle by the hand lever moving the rack to engage the linger normally therewith and simultaneously press the bell-crank lever against the stop to thereby slide the rack along the rod, resilient means for returning the rack and hand lever to their initial positions, a graduated scale member disposed along the travel of the hand lever for permitting the determining of the extent of the back'space movement. Y Y

5. A back spacing mechanism for typewriters, comprising, a linger rigidly connected to the carriage of the typewriter, an

elongated rod, a rack carried by this rod, and

slidable lengthwise of the same, a rockable spindle parallel withl the support, an arm interconnecting the spindle and support, a lixed stop, a pivotedbell-crank lever bearing at times against one end of the rack and the lixedy stop when rocking the spindle, a hand lll) lever, a graduated scale member for the hand lever, the hand lever being mounted on the spindle which lis displaceable angularly for moving therack to engage thenger normally therew1th,land simultaneously to press the bell-crank lever against the stop for slid-` ing the rack along the, rod a'distance corresponding to the angular displacement of the hand lever along the graduated scaleV member.

6. Aback spacing mechanism for typewriters wherein the carriage is back spaced by a hand operated'rod rigidly connected to the carriage, comprising a Vhand operated' rod, a finger positively eonnectable to the hand operated rod, a rod, a rack on this rod and slidable lengthwise thereof, a roekable spindle parallel with this rod, an arm interconnecting the spindle and rod, a fixed stop, a pivoted bell-crank lever bearing at times against one end of the rack and the fixed stop when rocking the spindle, a hand lever, y

a graduated scale member for the hand lever,

l0 the hand lever being arranged to rock'the corresponding to the angular displacement of 15 the hand lever along the graduated scale member. f

In testimony whereof I aiiix my signature.

HENRY PEETERS. 

